(1) Field of the Invention
This invention pertains to the conversion, especially reforming, of hydrocarbons in the presence of a catalyst composite. This invention also pertains to a new catalyst composition containing a platinum group component and a method for making the catalyst. Pertinent U.S. patent classifications for the subject matter of this invention include Class 208, Subclasses 64, 65, 133 and 143, and Class 252, Subclasses 461 and 466 PT--reforming of hydrocarbons with noble metal-containing catalysts.
The catalyst of this invention comprises a platinum group component, a tin component, an indium component and a halogen component with a porous support material. The catalyst comprises, on an element basis, about 0.6 or more wt. % indium. The catalyst is particularly useful in the catalytic reforming of hydrocarbons boiling in the gasoline range to produce in high yield a high octane reformate suitable for gasoline blending or a high aromatics content reformate suitable as a petrochemical feedstock.
(2) Description of the Prior Art
Many components have been added to platinum group-containing compositions to obtain catalysts with improved performance. For example, U.S. Pat. No. 2,814,599 discloses adding primary activating agents selected from the group of gallium, indium, scandium, yttrium, lanthanum, thallium and actinium, and optional secondary activating agents selected from the group of mercury, zinc and cadmium, as well as optional promoting agents selected from the alcohols and ketones, to obtain a platinum and/or palladium catalyst with improved reforming activity.
U.S. Pat. No. 3,745,112 discloses that tin is a good promoter for platinum group-containing reforming catalysts. This patent discloses a reforming catalyst comprising platinum, tin and halogen.
U.S. Pat. No. 3,892,657 discloses that indium is a good promoter for platinum group-containing reforming catalysts when the atomic ratio of indium to platinum is less than 1.0. This patent discloses also that a Group IVA component selected from the group of germanium, tin, and lead can be added to the acidic form of the indium-containing catalysts for reforming applications. The acidic form of this catalyst, then, comprises a platinum group component, optionally a Group IVA component, an indium component, a halogen component and a porous carrier material wherein the atomic ratio of indium to platinum is less than 1.0. In column 4, lines 10-12, this patent discloses that only when the atomic ratio of indium to platinum is about 0.1 to 1.0 is the beneficial interaction of indium with platinum obtained. In column 25, lines 33-37, this patent discloses that when the atomic ratio is 1.35 or more, the beneficial effect of indium is not obtained. No catalyst comprising platinum and tin disclosed in this patent contains more than 0.5 wt. % indium.
British Pat. No. 1 499 297 discloses a dehydrogenation catalyst comprising platinum, at least one of the elements gallium, indium and thallium, and an alkali metal, especially lithium or potassium, with alumina as the carrier material. The disclosure of this patent is not limited to any specific atomic ratio of gallium or indium or thallium to platinum. The catalyst disclosed in this patent does not contain a tin component.
Surprisingly, we have discovered that when indium is added to a platinum- and tin-containing reforming catalyst, best yields of C.sub.5 + liquid products are obtained when the catalyst comprises, on an elemental basis, about 0.6 or more wt. % indium. Furthermore, we have discovered that the beneficial effect of indium results from an interaction of indium with the porous support material, especially halogenated alumina, rather than from an interaction with the platinum group component as suggested by the prior art.